Flow properties of an Ahmed Body with different passive flow control methods

Abstract

A numerical simulation by utilizing the FloEFD software was carried out in order to investigate the flow topology formed on slant surface and wake region of an Ahmed Body with and without passive flow control techniques. The effects of those flow controllers on flow at the slant surface and wake region by influencing the flow topology as well as aerodynamic drag coefficient examined carefully. The numerical findings clearly revealed that the best performance in terms of providing the drag reduction obtained when sphere and hemispherical shape flow control techniques were applied at the rear part of slant surface of Ahmed Body. Sphere and hemispherical shape flow controllers positioned at the rear part of slant surface led to have drag reduction of 6% and 7%, respectively. Besides, the results of current study compared with the results obtained from published studies in the literature. It was clearly observed that they are consistent with each other even though they were found by different software.

Keywords

• Ahmed body
• Vehicle aerodynamics
• Passive flow control
• Drag reduction
• FloEFD

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